The ADH1B*2 allele, which is associated with particularly rapid ethanol oxidation, has shown protective effects against alcohol dependence in a variety of populations. In East Asians, in whom the ADH1B*2 allele is found at high frequency, it is protective against alcoholism (Chen et al. 1999a; Crabb et al. 2004; Hurley et al. 2002; Luczak et al. 2006; Thomasson et al. 1991; Whitfield 2002). For example, among Chinese living in Taiwan, the odds ratio for developing alcoholism for a person carrying a single ADH1B*2 allele is 0.19, and for a person carrying two ADH1B*2 alleles, 0.12, compared with a person carrying two ADH1B*1 alleles. (This calculation assumes that all subjects are homozygous for the ALDH2*1 allele.) In European or African populations, the ADH1B*2 allele is not very common but also provides protection against alcoholism (Whitfield 2002). Among people of Jewish descent, the ADH1B*2 allele is found at moderate frequencies and reduces binge drinking (Luczak et al. 2002) and risk for alcoholism (Hasin et al. 2002). Overall, the protective effect of ADH1B*2 appears to be weaker in European than in Asian populations
